FROM INTERNET:
MarkBratton111
The ES400 is a Motorola Solutions product. Solutions and Mobility are two separate companies, and I'm not sure that they support each other's products. Here's a link to ES400 support on the Motorola Solutions website, if you haven't been there yet. Perhaps they can help.FROM INTERNET
It is written in it`s mannual you can find it in attached link Motorola MOTOTRBO XPR 7550 User Manual or here is the video tutorial as well which is not for the same model but could may helps you
Hi. for now no body can give you the unlock code for Motorola network unlocking. Because motorola shuts down there server for unlock codes. The most effective & best way trending in Motorola network unlocking is Cable unlocking. You can get unlock your Motorola Moto G5S Plus XT1806 as well as any other Motorola phone by cable unlock. Take your phone to unlocking shop they will helps you. Or if you want to avail it online. Then i try 24x7unlockcodes.com for this & below procedure 24x7UnlockCode Network Unlock Code IMEI Unlock Code Unlock Code
The secret code for your Moto mobile phone
MOTOROLA
19980722 OK Master unlock code for phone and simlock
*#06# Display imei
*#300# OK List the software and hardware version
*#301# OK Full keypads functional test
*#303# OK Set default language to english
*#304# OK Set OFF engineering mode
*#304*19980722# Set ON engineering mode
*#307# OK Engineering test mode
*#311# OK Phone code changed to default code
*#402# OK Adjust display intensity/ contrast
*#403# OK List the manufacturing informations
*#302# OK Accoustict test
*#3370# Enhanced full rate
*#0000# OK Settings saved, restore set phone to default language
If it doesn't work, try to purchase the unlock codes from: http://www.ebay.co.uk/itm/Unlock-Code-Motorola-Moto-E-Moto-XT1022-XT1021-XT1541-XT1540-XT1524-/221439546897 or
https://theunlockr.com/2014/10/10/how-to-unlock-the-motorola-moto-e/